2010 Yamaha 150s using 2004 wiring harness

I have re-powered a 2004 Rosborough RF 246 with twin 2010 Yamaha f 150s. The original engines were 2004 Yamaha 115s. I used the original 2004 Yamaha wiring harness but used the 2010 gauges. Seems the only pins missing on the old harness are for the trim indicators. I'm fine without the indicators but I'm selling soon and would like to have it all functioning properly. Does anyone know if there is a way to run a jumper from the old harness to the new gauges? TIA.

What harness are you talking about?

The same ten pin main harness used for a 2004 model Yamaha works with a 2010 Yamaha. The ten pin harness does not have the wire for the trim within it.

A separate trim/oil harness is used to convey information to a Yamaha tachometer and trim gauge. Trim, low oil pressure, over temperature, check engine, low oil quantity main tank, low oil quantity remote tank, etc.

Thanks. I revisited the wiring to the Multi function gauges, and as you said it is a ten pin and it seems all pins are occupied. I think the trim sender wire is orange(?) and it is connected. Brand new senders and shop adjusted fingers just last week. Trim indicator still shows top bar flashing and no change when changing tilt. Its been like this since the re-power 4 years ago. The mechanic felt certain it was a discrepancy between 2010 motors and 2004 harness but now I don't think that's the case. It's just sticking in my craw that they aren't functioning. Electrical work is my weakness. Any and all ideas please. Thanks

Trim sender wire is pink. Pink on the motor. Pink in the trim/oil harness, pink to the M/F tachometer.

Orange from the tachometer is 5 volts for a three wire sender. Your 2010 motor uses a two wire sender.

Are these F150's/F115's we are talking about or two stroke 150's/115's?

I love it when we have no idea the model of the motor that is being discussed.

boscoe said:

Are these F150's/F115's we are talking about or two stroke 150's/115's?

I love it when we have no idea the model of the motor that is being discussed.

Click to expand...

Ha! Sorry. 2010 Yamaha F150 4 stroke. Thanks for the correction on the wire color.

Do you have the tachometer with two four pin nylon connectors? I suspect so if it has an orange wire. It will connect to a 2010 model as per the following diagram.